I came upon a 97B several months ago at a local store and made a trade. After shooting (and enjoying) the gun I decided I really wanted a 97BD for commonality of controls with my SP-01 Tactical. The 97BD was ordered and now sits in my collection. I still haven't sold the 97B and I decided to compare the two guns. I've noticed some unexpected (mostly superficial) differences between the two models (besides the decocker, rubber grips and night sights). The barrel bushing on the BD has alignment notches cut around its entire circumference instead of just the one alignment notch on the B. The rear sight of the 97BD is noticeably higher than the rear sight of the B. I chalked the sight difference up to different brands of sights and intended target distance.
So are these differences common between all 97B and BDs or did I come across a new or old version of one or the other? Did that even make any sense? Both guns shoot just fine and these questions are just out of wild curiosity.